Amazon Route 53 is a highly available and scalable cloud Domain Name System (DNS) web service.

Amazon Route 53 effectively connects user requests to infrastructure running in AWS – such as Amazon EC2 instances, Elastic Load Balancing load balancers, or Amazon S3 buckets – and can also be used to route users to infrastructure outside of AWS. You can use Amazon Route 53 to configure DNS health checks to route traffic to healthy endpoints or to independently monitor the health of your application and its endpoints.

Amazon Route 53 Traffic Flow makes it easy for you to manage traffic globally through a variety of routing types, including Latency Based Routing, Geo DNS, and Weighted Round Robin—all of which can be combined with DNS Failover in order to enable a variety of low-latency, fault-tolerant architectures. Using Amazon Route 53 Traffic Flow’s simple visual editor, you can easily manage how your end-users are routed to your application’s endpoints—whether in a single AWS region or distributed around the globe. Amazon Route 53 also offers Domain Name Registration – you can purchase and manage domain names such as example.com and Amazon Route 53 will automatically configure DNS settings for your domains.

Amazon Route 53 currently supports the following DNS record types:

• TXT (text record)
• SRV (service locator)
• SPF (sender policy framework)
• SOA (start of authority record)
• PTR (pointer record)
• NS (name server record)
• MX (mail exchange record)
• CNAME (canonical name record)
• AAAA (IPv6 address record)
• A (address record)
• Additionally, Amazon Route 53 offers ‘Alias’ records (an Amazon Route 53-specific virtual record). Alias records are used to map resource record sets in your hosted zone to Amazon Elastic Load Balancing load balancers, Amazon CloudFront distributions, AWS Elastic Beanstalk environments, or Amazon S3 buckets that are configured as websites. Alias records work like a CNAME record in that you can map one DNS name (example.com) to another ‘target’ DNS name (elb1234.elb.amazonaws.com). They differ from a CNAME record in that they are not visible to resolvers. Resolvers only see the A record and the resulting IP address of the target record.

 

Amazon Route 53 does not support DNSSEC at this time.

Amazon Route 53 offers a special type of record called an ‘Alias’ record that lets you map your zone apex (example.com) DNS name to your ELB DNS name (i.e.elb1234.elb.amazonaws.com). IP addresses associated with Amazon Elastic Load Balancers can change at any time due to scaling up, scaling down, or software updates. Route 53 responds to each request for an Alias record with one or more IP addresses for the load balancer. Queries to Alias records that are mapped to ELB load balancers are free. These queries are listed as “Intra-AWS-DNS-Queries” on the Amazon Route 53 usage report.

Route53 has a security feature that prevents internal DNS being read be external sources. The work around is to create a EC2 hosted DNS instance that does zone transfers from the internal DNS, and allows it’self to be queried by external servers

DNS Routing Policy 

• Weighted Round Robin (WRR)
• Latency Based Routing (LBR)